The present invention relates to a block toy; and more particularly to the structure of a block toy utilized in constructing a running toy. Typically, children and others use block toys by connecting several blocks (or components) into a desired shape such as a vehicle, an animal, or any other shape. A component of a block toy is a block unit or housing. A block unit or housing has a geometrical shape such as a rectangular parallelopiped, cylinder or sphere. Typically, block units or housings are adapted for connecting various block units or housings together into a static shape such as described above.
Running toys can also be constructed using block units such running toys combine block units with a power device to drive movable members of the block units. Commonly, the power device comprises a motor and the movable members comprise wheels. The appearance of such block toys, however, is not desirable because a power transmission mechanism must be attached to the block units after the completion of a running toy block assembly. The transmission mechanism delivers a drive force from the power device to the wheels. In addition, unsightly support members must be employed to hold a power transmission mechanism positioned outside of the unit blocks.